Television base casting

ABSTRACT

The PTV cabinetry of the present invention utilizes an integrally weighted base that enables the cabinet to satisfy load bearing and tip over standards without requiring the addition of separate weights. The base preferably includes a raised region and at least one lower region. Fill material is poured into the base, and substantially within the lower region, and allowed to set and harden. The fill material used is any suitable material having a density sufficient to act as a weight, such as, e.g., a concrete and fiber mixture or a metallic material. The raised region of the base may include a plurality of openings that allows heat to dissipate from within the interior space of the cabinet. The integrally weighted base of the present invention replaces a typical flat bottom panel of a typical PTV cabinet and further eliminates the need for attaching separate weights onto a bottom panel of a typical PTV cabinet.

FIELD OF THE INVENTION

[0001] The present invention relates generally to projection television sets, and more particularly to an integrally weighted base that prevents the tip over of a projection television enclosure.

BACKGROUND

[0002] Projection televisions (PTVs) or “big screen” TVs are a popular alternative to traditional picture tube televisions because they provide comparably larger viewable screens that cannot be efficiently produced using conventional picture tubes. PTV cabinets are presently designed to hold electrical and optical components, as required, to decipher and project a television picture on a screen generally on the front of the cabinet. The most common PTV on the market today projects pictures created via appropriate electrical and optical components onto a mirror within a box containing the entire apparatus so that the picture reflected to a screen is as large as possible for the volume occupied by the cabinet enclosing it. Currently, PTV screens typically range in size from about 45 to about 73 inches along their diagonal, while the cabinets typically range in size from about 48 inches to over 65 inches in height, from about 38 inches to over 65 inches in width, and from about 22 inches to over 29 inches in depth. The cabinets are assembled in an aesthetically appealing manner as required to hold the electrical components, light generator(s), and lenses, mirror and screen in the relationship required to obtain the desired televised picture.

[0003] Most PTVs marketed today include a cabinet constructed from multiple pieces of particleboard cut and glued together. Some cabinets also have plastic components held to the basic cabinet structure with screws or other fasteners. The number of plastic components and particleboard pieces needed to form such cabinets typically range in excess of fifty (50) pieces. Because of the size of PTVs, and the particleboard from which the cabinets are typically constructed, PTVs tend to be quite heavy and difficult to maneuver.

[0004] Alternative methods of manufacture are available that may reduce the overall weight of these cabinets, the number of components necessary to construct such cabinets, and the overall depth of the cabinet. For instance, injection molding could be used to form such cabinets out of plastic. Another alternative would be to vacuum form the cabinetry out of plastic. The use of lighter weight materials to manufacture PTV cabinets leads to an additional problem in that the lighter weight cabinets are easier to tip over relative to the traditional particle board cabinets. For example, the manufacture of a cabinet that is smaller in depth relative to a traditional cabinet results in a cabinet with a smaller footprint to support a cabinet that is substantially the same height as a traditional PTV cabinet with a larger footprint. This results in variety of safety issues since, e.g., a PTV cabinet must meet load bearing, or tip over, standards. Current standards, such as, e.g., Underwriter's Laboratories load standards, require that a PTV cabinet must be able to withstand 25 lbs of force without tipping over. Without the addition of some weight to the base of a lighter, thinner PTV cabinet, the thinner PTV cabinet would be more likely to fail the UL tip over test than a traditional particle board cabinet. To address this problem, those skilled in the art currently add counterweights to the bottom of the lighter weight cabinets, which have generally flat bases formed from wood or particle board, in order to enable these cabinets to withstand at least 25 lbs of force without tipping over. Typically, the amount of weight added to the bottom of a PTV cabinet is determined using the following formula: Added Weight=(25 lbs)(Height of the Cabinet/Depth of the Cabinet).

[0005] Turning to FIG. 1, a conventional cabinet 10 of a PTV 50 is illustrated. The conventional cabinet 10 includes top 12, bottom 14, front 16, and rear 18 panels. Side panels connecting the front 16 and rear 18 panels are also included, but not illustrated. The conventional cabinet 10 is typically divided by an internal wall 24 into two compartments, i.e., an upper 20 and a lower 22 compartment. Cathode ray tubes (CRTs) 26 and printed wiring boards (PWBs) 30 are typically mounted in the lower compartment 22, while a mirror M and a screen S are mounted in the upper compartment 20. At least one projection lens 28 typically extends from the lower compartment 22 into the upper compartment 20 through the internal wall 24. The upper compartment 20 is typically tightly sealed from the lower compartment 22 to protect the inside of the upper compartment 20 from dust and other foreign materials. The lower compartment 22 typically includes one or more sets of ventilation holes to exhaust heat radiating from the CRTs 26 and the PWBs 30. As shown, the lower compartment 22 includes a first set of holes 32 positioned adjacent the top of the lower compartment 22 and a second set of holes 34 positioned adjacent the bottom of the lower compartment 22. When the cabinet 10 is constructed using lighter weight materials and methods, such as those previously discussed, weights 36 must be positioned in the lower compartment 22, and normally on top of the bottom panel 14, in order to balance the cabinet 10. Currently, weights 36, which may be metal bricks, additional particle board base pieces, or any other suitable counterweights, are tied or otherwise physically attached to the bottom panel 14 of the cabinet 10. The number of weights 36 used in the cabinet 10, to enable the cabinet 10 to pass the UL tip over test, is determined with the aforementioned formula.

[0006] The current methods for balancing a thinner, lighter PTV cabinet result in several disadvantages. For example, the use of additional particle board bases to increase the weight and stability of these cabinets often requires the additional use of forest products, thereby contributing to long term environmental deleterious effects. Also, the additional step of adding a separate weight to a cabinet increases the complexity and cost of producing the lighter weight PTV cabinets. There is also a danger that the weights may not be properly secured to the cabinet during construction, thereby resulting in safety issues should the weights become dislodged during transport of the cabinet, or during the lifetime of the cabinet. For example, the weights may become dislodged and repositioned in an area that causes the cabinet to become unbalanced and more likely to tip over.

[0007] Those skilled in the art have failed to provide for a light weight PTV cabinet capable of passing standard load tests without the addition of costly counterweights. Thus, it would be desirable to provide for a PTV cabinet that is easy and less costly to manufacture, mitigates environmental damage due to a decreased reliance on wood for a counterweight, is less vulnerable to manufacturing irregularities, and reliably meets load/tip over standards for PTV cabinets.

SUMMARY OF THE INVENTION

[0008] The present invention is directed to an improved enclosure or cabinet for PTVs. The PTV cabinet of the present invention includes an integrally weighted base formed with fill material that acts to stabilize the cabinet and enables the cabinet to satisfy load and tip over standards. The PTV cabinet of the present invention is particularly useful when implemented as part of a lighter weight PTV cabinet, but is also capable of being used with traditional, wood-based PTV cabinets.

[0009] In one particularly innovative aspect of the present invention, a cabinet for a PTV includes a top portion housing a mirror, a plurality of CRTs, and a projection lens. The top portion preferably includes a top panel, a front panel, a rear panel, and side panels extending between the front and rear panels. Attached to the top portion, and opposite the top panel of the cabinet, is a base having at least one raised area, each raised area having a top surface, at least one lower region adjacent to each raised area, and a fill material deposited into each lower region. The base provides stability to the cabinet and enables the cabinet to satisfy standard load bearing requirements. The top surface of the raised region may include a plurality of vent openings allowing heat built up within the cabinet to dissipate therethrough. In another embodiment, additional elevated regions are present on the base that allow for components to be securably attached to the base. The fill material is preferably a material having a density greater than wood or of the panels of the cabinet. Exemplary fill materials include a concrete/fibrous material mixture and a metallic material.

[0010] In another aspect of the present invention, a method of manufacturing a television cabinet having an integrally weighted base includes manufacturing a base having at least one raised region, at least one lower region adjacent each raised region, and a plurality of openings on a top surface of each raised region. A fill material, which may be any of the aforementioned materials, such as, e.g., a concrete/fibrous material mixture or a metallic substance, is poured into the base and allowed to set or harden. The fill material is typically poured substantially within the lower regions of the base, although some fill material may accumulate atop the raised region. After the fill material has set, the fill material is ground down such that the fill material is substantially level with the top surface of the raised region.

[0011] Other objects and features of the present invention will become apparent from consideration of the following description taken in conjunction with accompanying drawings.

DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 is a side view of a projection television set of the prior art.

[0013]FIG. 2 is a side view of one embodiment of a PTV cabinet, having an integrally weighted base, of the present invention.

[0014]FIG. 3 is a side view of the base of the PTV cabinet of the present invention illustrated in FIG. 2.

[0015]FIG. 4 is a side view of another embodiment of the base of a PTV cabinet of the present invention.

[0016]FIG. 5A is a top view of an embodiment of the base of a PTV cabinet of the present invention having parallel, length-wise openings.

[0017]FIG. 5B is a top view of an embodiment of the base of a PTV cabinet of the present invention having parallel, width-wise openings.

[0018]FIG. 5C is a top view of an embodiment of the base of a PTV cabinet of the present invention having a plurality of circular openings.

[0019]FIG. 5D is a top view of an embodiment of the base of a PTV cabinet of the present invention having diagonally parallel openings.

[0020]FIG. 6 is a side view of an embodiment of the base of a PTV cabinet of the present invention having a plurality of raised regions.

DETAILED DESCRIPTION

[0021] The present invention is applicable to cabinets for a variety of devices or display devices that are subject to a standardized load bearing test. The following discussion, however, focuses on cabinets for PTV sets for exemplary purposes only. In one preferred embodiment, a base having a frame and fill material disposed within the frame is provided. The base is configured to conform to the shape of a cabinet to which it is to be attached, forming the bottom portion of the cabinet. Alternatively, the base may be formed with the fill material in the absence of a frame.

[0022] Illustrated in FIG. 2 is one embodiment of a cabinet 110 of a PTV 100 using the present invention. The cabinet 110 includes a top panel 112, a front panel 116, a rear panel 118, and side panels (not shown) extending between the front 116 and rear 118 panels and in further connection with the top panel 112. Furthermore, a cabinet suitable for use with the present invention is not limited to one having a front, rear, and two side panels. Rather, the present invention is capable of use with a cabinet that has any plurality of side panels, such as, e.g., a cabinet shaped like an octagon. Additionally, a cabinet suitable for use with the present invention is not limited to a square or rectangle shaped cabinet but may be any suitable shape, such as, e.g., a trapezoidal shaped cabinet. The present invention is molded to conform with the specific shape of the cabinet that incorporates the invention.

[0023] Turning back to FIG. 2, the cabinet 110 is preferably divided by an internal wall 124 into an upper 120 compartment and a lower 122 compartment. CRTs 126 and PWBs 130 are preferably mounted in the lower compartment 122, and a mirror M and a screen S are preferably mounted in the upper compartment 120. At least one projection lens 128 preferably extends from the lower compartment 122 into the upper compartment 120 through the internal wall 124. The upper compartment 120 is preferably tightly sealed from the lower compartment 122 in order to protect the inside of the upper compartment 120 from dust and other foreign materials that might otherwise be introduced from the lower compartment 122. The cabinet 110 is preferably constructed using light weight materials and methods, such as, e.g., molded plastic foam components formed from expanded polystyrene or phenolic that is sandwiched between coatings of an appropriate structural material such as plastic. Appropriate materials and methods to construct a cabinet using light weight materials are further described in copending U.S. patent application Ser. No. 09/643,892 to Lowe entitled “Foam Cabinetry for Electronic Devices,” which is fully incorporated herein. Alternatively, the top panel 112, front panel 116, rear panel 118, and side panels (not shown) of the cabinet 110 may be constructed of particle board, or another wood-based material.

[0024] Rather than a flat bottom panel typical of the prior art, such as, e.g., bottom panel 14 of cabinet 10 illustrated in FIG. 1, the cabinet 110 using the present invention includes a base 150. The base 150 provides a footprint upon which the cabinet 110 is balanced. The base 150 preferably includes at least one raised region or area 152 and at least one lower region 154 adjacent each raised region 152. The base 150 is preferably molded from a plastic compound or from a metallic compound. If the base 150 is formed from a metallic compound, the base 150 further acts as a radiation shield, i.e., a metallic base 150 provides an additional function of being able to reduce the emission of electromagnetic radiation through the lower compartment 116 of the cabinet 110. In one embodiment, the base 150 is formed by placing the compound that will comprise the frame 151 of the base 150, such as metal or plastic, into a master mold. The compound placed into the master mold is preferably initially in a substantially liquid state. After the compound hardens or sets, the compound is removed from the mold. The hardened compound forms the frame 151 of the base 150.

[0025] Turning to FIG. 3, a close-up, side view of one embodiment of the base 150 is shown. The embodiment of the base 150 illustrated in FIG. 3 includes the frame 151 and fill material 158 set within the frame 151 of the base 150. The base 150 further includes a plurality of openings 156 on a top surface of the raised region 152 of the frame 151. When present, the openings 156 allow for heat radiating from the components of the PTV, such as, e.g., the CRTs 126 and the PWBs 130, to dissipate from the lower compartment 116. To further increase heat dissipation from the lower compartment 116, a set of holes 132 positioned on the rear panel 118 is optionally provided. One skilled in the art would understand that the location of the set of holes 132 may vary depending on the desired heat dissipation effect.

[0026] A fill material 158 is poured into the frame 151 of the base 150. Preferably, the fill material 158 is poured substantially within the lower region 154 of the frame 151, although it is to be expected that some fill material 158 may also contact the raised region 152 during this process. In one embodiment, the fill material 158 is a concrete mixture. When concrete is used as the fill material, a fibrous material may be added to the concrete to provide structure within the concrete and to increase the tensile properties of the fill material. In another embodiment, the fill material 158 is a metallic material. In still other embodiments, the fill material 158 may be any other material that possesses a density greater than the material used to construct the panels of the cabinet 110, and therefore a density and resultant weight sufficient to balance the cabinet 110. For example, when the panels of the cabinet 110 are constructed of wood or particle board, the fill material 158 must exhibit a density greater than the density of the material used for the panels.

[0027] After the fill material 158 is poured into the frame 151, and into the lower region 154 of the frame 151, the fill material 158 is allowed to set or cure. Preferably, once the fill material 158 solidifies, the top surface of the fill material 158 is ground down such that the top surface of the fill material 158 is substantially level with the top surface of the raised region 152. The grinding process is preferably accomplished through mechanically abrasive methods, although chemicals may also be used during this process. In embodiments of the base 150 having the plurality of openings 156, any fill material 158 covering the openings 156 is removed from the top surface of the raised region 152 during the grinding process.

[0028] The base 150 is attached to the front panel 116, the rear panel 118 and the side panels (not shown) of the cabinet 110, opposite the top panel 112 of the cabinet 110, to form the bottom surface of the cabinet 110. The base 150 is secured to the front panel 116, rear panel 118, and side panels (not shown) using any suitable attachment method, such as, e.g., a suitable adhesive or brackets.

[0029] The base 150 allows the cabinet 110 to be weighted in a manner suitable for satisfying industry standard load tests, such as, e.g., the UL tip over test, without the need for placing additional, individual weights, see, e.g., weights 36 of cabinet 10 in FIG. 1, inside the cabinet, unlike prior art cabinets. One advantage of base 150 over the prior art is that the possibility of individual counterweights, i.e., weights 36 of cabinet 10 in FIG. 1, becoming detached during manufacture, transport, or the life of the cabinet 10 is eliminated. Consequently, the ability of a cabinet using base 150 to satisfy standardized load bearing tests is ensured.

[0030] Turning now to FIG. 4, another embodiment of the base 250 of the present invention is illustrated. Base 250 has a frame 251 that further includes a plurality of elevated portions 252 disposed within the lower regions 154 of the frame 251. Although two elevated portions 252 are illustrated, any multiple number of elevated portions 252 may be implemented in base 250. The elevated portions 252 are configured for securably attaching thereto a component of the PTV, such as, e.g., the PWB 130, to the base 250. Each portion 252 includes an opening (not shown) configured for securably inserting an attachment element, such as, e.g., a screw, therein. In practice, for example, the PWB 130 is placed atop the elevated portions 252 prior to the coupling of the base 250 to the cabinet, and attachment elements are inserted through the PWB 130 and into each opening of each respective portion 252. As a result, the PWB 130 is secured to the base 250.

[0031]FIGS. 5a-5 d illustrate top views of several embodiments of the present invention, showing possible configurations for the openings 156 of the base 150. FIG. 5a illustrates a base 150 a having openings 156 a that are oriented parallel relative to each other and also extend along the length of a raised region 152 and of the base 150 a. FIG. 5b illustrates a base 150 b having openings 156 b that are oriented parallel to each other but that extend along the width of a raised region 152 and of the base 150 b. FIG. 5c illustrates a base 150 c having openings 156 c that are circular in shape and that are dispersed throughout a raised region 152 of base 150 c. FIG. 5d shows a base 150 d having diagonally oriented openings 150 d on the raised region 152. Other configurations and shapes of openings are also capable of being implemented on the base of the present invention. One skilled in the art would appreciate that the configurations and shapes of the openings of the raised region 152 may vary based upon the desired heat dissipation effect, for example.

[0032] The present invention also provides for PTV cabinet with a base having a plurality of raised regions. Turning to FIG. 6, a base 350 is illustrated that includes frame 351 having a plurality of raised regions 352. Although two raised regions 352 are shown, it is envisioned that many multiple numbers of raised regions 352 may be implemented in base 350. As with the previous embodiments of the base, the frame 351 of base 350 further includes lower regions 354 adjacent to each raised region 352. Fill material 358 is poured into the frame 351, and substantially within the lower regions 354, allowed to set or harden, and then ground down to be substantially level with the top surface of the raised regions 352. The base 350 illustrated in FIG. 6 also includes a plurality of openings 356, to allow for heat dissipation, on the top surface of the raised regions 356. Any fill material 358 that may have accumulated over these openings 356 during the pour and set processes are ground away in order to keep the openings 356 unobstructed.

[0033] The particular examples set forth herein are instructional and should not be interpreted as limitations on the applications to which those of ordinary skill are able to apply this device. Modifications and other uses are available to those skilled in the art which are encompassed within the spirit of the invention as defined by the scope of the following claims. 

What is claimed is:
 1. A method of manufacturing a television cabinet having a weighted base, comprising: forming a base having a raised region, the raised region having a top surface, and a lower region, pouring a fill material into the base, and grinding the fill material so that the top of the material is substantially level with the top surface of the raised region of the base.
 2. The method of claim 1 further comprising the step of securably attaching the base to the television cabinet.
 3. The method of claim 1, wherein the raised region further includes a plurality of openings disposed on the top surface of the raised region.
 4. The method of claim 1, wherein the fill material is a mixture of concrete and fibrous material.
 5. The method of claim 1, wherein the fill material comprises a material having a density greater than the density of wood.
 6. The method of claim 1, wherein the fill material is poured substantially into the lower portion of the base.
 7. The method of claim 1, wherein the base is formed of metal.
 8. The method of claim 1, wherein the base is formed of plastic.
 9. The method of claim 1, wherein the raised region is located at a center location of the base.
 10. A method of manufacturing a television cabinet having a weighted base, comprising: manufacturing a base having at least one raised region, each raised region having a top surface, at least one lower region adjacent each raised region, and a plurality of openings on each top surface of each respective raised region, pouring a fill material into the base, allowing the fill material to harden, and grinding the fill material so that the top of the fill material is substantially level with the top surface of each raised region.
 11. The method of claim 10, wherein the base is constructed with metal.
 12. The method of claim 10, wherein the base is constructed with a plastic material.
 13. The method of claim 10, wherein the fill material comprises a mixture of concrete and fibrous material.
 14. The method of claim 10, wherein the fill material comprises a metallic material.
 15. The method of claim 10, wherein the base further comprises a plurality of elevated portions within each lower region, wherein each respective elevated portion includes an opening configured for securably inserting an attachment element therein.
 16. A cabinet for a projection television comprising: a cabinet portion configured to house a mirror, a plurality of CRTs, and a projection lens, the cabinet portion having a top panel, a front panel, a rear panel, and side panels in connection with the top, front, and rear panels, and a base attached to the front and rear panels of the cabinet portion, opposite the top panel of the cabinet portion, having a raised area with a top surface, at least one lower region adjacent the raised area, and a fill material deposited into the at least one lower region adjacent the raised area of the base.
 17. The cabinet of claim 16, wherein a top surface of the fill material is level with the top surface of the raised area.
 18. The cabinet of claim 16, wherein the top surface of the raised region includes a plurality of openings.
 19. The cabinet of claim 16, wherein the base further comprises a plurality of elevated portions, each elevated portion having an opening configured for securably inserting an attachment element therein.
 20. The cabinet of claim 16, wherein the elevated portions are disposed within a lower region of the base.
 21. The cabinet of claim 16, wherein the fill material comprises a mixture of concrete and fibrous material.
 22. The cabinet of claim 16, wherein the fill material comprises a metallic material.
 23. The cabinet of claim 16, wherein the fill material comprises a material with a density greater than the density of the front, rear, top, and side panels of the cabinet portion.
 24. The cabinet of claim 16, wherein the base comprises a metallic material.
 25. The cabinet of claim 16, wherein the base comprises a plastic material.
 26. A cabinet for a projection television comprising: a cabinet portion configured to house a mirror, a plurality of CRTs, and at least one projection lens, the cabinet portion having a top panel, a front panel, a rear panel, and side panels attached to the top, front, and rear panels, and a base attached to the front, rear, and side panels of the cabinet portion, opposite the top panel of the cabinet portion, having at least one raised area, at least one lower region adjacent each raised area, and a fill material deposited into each lower region, wherein each raised area further includes a top surface.
 27. The cabinet of claim 26, wherein the fill material further comprises a top portion that is substantially level with the top surface of each raised area.
 28. The cabinet of claim 26, wherein each top surface of each raised region includes a plurality of openings.
 29. The cabinet of claim 26, wherein the base further comprises a plurality of elevated portions, each elevated portion having an opening configured for securably inserting an attachment element therein.
 30. The cabinet of claim 29, wherein the elevated portions are disposed within a lower region of the base.
 31. The cabinet of claim 26, wherein the fill material comprises a mixture of concrete and fibrous material.
 32. The cabinet of claim 26, wherein the fill material comprises a metallic material.
 33. The cabinet of claim 26, wherein the fill material comprises a material having a density greater than the density of the front, rear, top, and side panels of the cabinet portion.
 34. The cabinet of claim 26, wherein the base comprises a metallic material.
 35. The cabinet of claim 26, wherein the base comprises a plastic material. 